Method BuildIntersectList

static_libs/clipper/clipper.cpp:2836–2880

//------------------------------------------------------------------------------

void Clipper::BuildIntersectList(const cInt topY)
{
    if (!m_ActiveEdges)
        return;

    //prepare for sorting ...
    TEdge* e = m_ActiveEdges;
    m_SortedEdges = e;
    while (e) {
        e->PrevInSEL = e->PrevInAEL;
        e->NextInSEL = e->NextInAEL;
        e->Curr.X = TopX(*e, topY);
        e = e->NextInAEL;
    }

    //bubblesort ...
    bool isModified;
    do {
        isModified = false;
        e = m_SortedEdges;
        while (e->NextInSEL) {
            TEdge* eNext = e->NextInSEL;
            IntPoint Pt;
            if (e->Curr.X > eNext->Curr.X) {
                IntersectPoint(*e, *eNext, Pt);
                if (Pt.Y < topY)
                    Pt = IntPoint(TopX(*e, topY), topY);
                IntersectNode* newNode = new IntersectNode;
                newNode->Edge1 = e;
                newNode->Edge2 = eNext;
                newNode->Pt = Pt;
                m_IntersectList.push_back(newNode);

                SwapPositionsInSEL(e, eNext);
                isModified = true;
            } else
                e = eNext;
        }
        if (e->PrevInSEL)
            e->PrevInSEL->NextInSEL = nullptr;
        else
            break;
    } while (isModified);
    m_SortedEdges = nullptr; //important
}
//------------------------------------------------------------------------------

void Clipper::ProcessIntersectList()